[jira] [Work started] (TRAFODION-1715) UPDATE STATISTICS allocates memory even when a SAMPLE table is used

["David Wayne Birdsall (JIRA)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/TRAFODION-1715?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Work on TRAFODION-1715 started by David Wayne Birdsall.
-------------------------------------------------------
> UPDATE STATISTICS allocates memory even when a SAMPLE table is used
> -------------------------------------------------------------------
>
>                 Key: TRAFODION-1715
>                 URL: https://issues.apache.org/jira/browse/TRAFODION-1715
>             Project: Apache Trafodion
>          Issue Type: Bug
>          Components: sql-cmp
>         Environment: All
>            Reporter: David Wayne Birdsall
>            Assignee: David Wayne Birdsall
>
> UPDATE STATISTICS attempts to use an internal sort when possible. It estimates how much memory it has available to it, and estimates how much memory is needed to store the sample data. It then attempts to allocate this memory. If it fails to get everything it needs, it appears to retain what memory it has allocated, but then runs a sample table load query. Thus, memory has been allocated in the master executor process that might have been useful to the load query. It would have been better perhaps to release this memory, and attempted to reaquire it later.



--
This message was sent by Atlassian JIRA
(v6.4.14#64029)